Red blood cell transfusion in newborn infants

Question 1

What are the most frequent indications for RBC transfusions in the newborn?

Answer 1

1. Acute treatment of perinatal or surgical hemorrhagic shock
   (placental hemorrhage, twin-to-twin transfusion, fetomaternal hemorrhage, velamentous insertion of the cord or cord rupture)
   (Rx NS 10-20 ml/kg then emergency O Rh- pRBCs, initial 1 min push of 20 ml, then 10 ml/kg/hr)
2. ‘Top-ups’ for the recurrent correction of anemia of prematurity

Question 2

What are the main risks of transfusion?

Answer 2

1. Transfusion-transmitted infections (viral*, bacterial, parasitical, prional)
2. The adverse effects of leukocytes (immunomodulation, GVHD, TRALI, alloimmunization**)
3. Acute volume or electrolyte disturbances
4. Blood group incompatibilities (often mistransfusion errors)

• The combined risk of RBC contamination with viruses (e.g. Hep A, B and C, HIV and HTLV) is of the order of one in one to 1.3 million
• The risk of CMV infection is reduced by universal leukoreduction, practiced in Canada since 1998
• *Hemolytic transfusion reactions are also rare in the newborn; maternal isohemagglutinins are occasionally present in the first 2 months, but infant alloantibodies are rarely formed <6 months of age. Start cross-matching at 4 months.

Question 3

Stored pRBCs last ___ days and have a hematocrit of ___%. Pretransfusion testing consists of ___ grouping, ___ typing and screen for maternal ___. Transfusion volumes are typically ___ to ___ ml/kg.

Answer 3

42; 60; ABO; Rh; antibodies (indirect and direct antiglobulin tests); 10-20.

Question 4

What is a major risk of rapid and massive transfusion?

Answer 4

Hyperkalemia

Also consider dilution of coagulation factors, so use combined replacement with FFP

Question 5

What is anemia of prematurity?

Answer 5

An exacerbation of the physiological anemia of the newborn, combining a suppressed postnatal response to EPO, increased blood sampling, short RBC span in the newborn and the rapid increase in blood volume with growth.
The rapid decline in Hgb is most severe in infants of low GA. >90% of ELBW infants are transfused, and they receive an average of ~5 transfusions each

Question 6

What did the PINT study show?

Answer 6

The Premature Infants in Need of Transfusion (PINT) study found that restrictive/low transfusion thresholds did not have a significant impact on the combined outcomes of mortality or major morbidities at first hospital discharge (BPD, hemorrhagic or ischemic brain injury, or severe ROP)

Minimum Hgb by age
Week 1 of life: 100 (115 if resp support)
Week 2 of life: 85 (100 if resp support)
Week 3+ of life: 75 (85 if resp support)

(Lower Hgb than this may lead to cognitive impairment)

Question 7

What are two other ways to support/increase hemoglobin other than RBC transfusion?

Answer 7

1. Iron (2mg/kg/day starting at 4-6 weeks of age at the onset of reticulocytosis can result in higher Hrb at 6 months)
2. EPO (may slightly reduce need for transfusion but can significantly increase risk of severe ROP, use only with families that refuse consent to transfusion)